Sequence data from mitochondrial and nuclear small subunit
rDNA were used to estimate phylogenetic relationships of
cantharelloid and clavarioid Homobasidiomycetes. Sixty-five
diverse Homobasidiomycete species were investigated,
including 23 cantharelloid and clavarioid species. Although
nodes deep in the tree could not be resolved, four lineages
containing cantharelloid and clavarioid fungi were
identified. (i) Cantharellaceae (Cantharellus,
Craterellus) is closely related to Hydnum, which
is toothed, Stichoclavaria, which is a simple club,
and Clavulina, which is coralloid. These taxa all have
stichic nuclear division, which is a synapomorphy supporting
this clade. (ii) Clavariadelphus is closely related to
Gomphus and Ramaria. This relationship is
supported by green reactions of sporocarps treated with iron
salts, which is reflective of the presence of the compound
pistillarin. The nearest relatives of these cantharelloid and
clavarioid fungi are gasteromycetes, including the earth star
Geastrum, the stinkhorn Pseudocolus, and the
cannon-ball fungus Sphaerobolus. (iii) The
clavarioid fungi Clavaria, Clavulinopsis, Pterula, and
Typhula appear to be derived from the lineage that
contains most of the gilled fungi. (iv) Clavicorona is
closely related to Auriscalpium, which is toothed, and
Lentinellus, which is gilled. This lineage is united
by amyloid spore ornamentation. Although these results
suggest that there has been extensive convergence in fruiting
body morphology, certain anatomical and biochemical features
appear to be phylogenetically informative, notably stichic
nuclear division, presence of pistillarin, and cyanophily or
amyloidity of spore ornamentation.